(function($) {

    /**
     * Initialize editor libraries.
     *
     * Some editors need to be initialized before the DOM is fully loaded. The
     * init hook gives them a chance to do so.
     */
    Drupal.wysiwygInit = function() {
        // This breaks in Konqueror. Prevent it from running.
        if (/KDE/.test(navigator.vendor)) {
            return;
        }

        jQuery.each(Drupal.wysiwyg.editor.init, function(editor) {
            // Clone, so original settings are not overwritten.
            this(jQuery.extend(true, {}, Drupal.settings.wysiwyg.configs[editor]));
        });
    };

    /**
     * Attach editors to input formats and target elements (f.e. textareas).
     *
     * This behavior searches for input format selectors and formatting guidelines
     * that have been preprocessed by Wysiwyg API. All CSS classes of those elements
     * with the prefix 'wysiwyg-' are parsed into input format parameters, defining
     * the input format, configured editor, target element id, and variable other
     * properties, which are passed to the attach/detach hooks of the corresponding
     * editor.
     *
     * Furthermore, an "enable/disable rich-text" toggle link is added after the
     * target element to allow users to alter its contents in plain text.
     *
     * This is executed once, while editor attach/detach hooks can be invoked
     * multiple times.
     *
     * @param context
     *   A DOM element, supplied by Drupal.attachBehaviors().
     */
    Drupal.behaviors.attachWysiwyg = function(context) {
        // This breaks in Konqueror. Prevent it from running.
        if (/KDE/.test(navigator.vendor)) {
            return;
        }

        $('.wysiwyg:not(.wysiwyg-processed)', context).each(function() {
            var params = Drupal.wysiwyg.getParams(this);
            var $this = $(this).addClass('wysiwyg-processed');
            // Directly attach this editor, if the input format is enabled or there is
            // only one input format at all.
            if (($this.is(':input') && $this.is(':checked')) || $this.is('div')) {
                Drupal.wysiwygAttach(context, params);
            }
            // Attach onChange handlers to input format selector elements.
            if ($this.is(':input')) {
                $this.change(function() {
                    // If not disabled, detach the current and attach a new editor.
                    Drupal.wysiwygDetach(context, params);
                    Drupal.wysiwygAttach(context, params);
                });
                // IE triggers onChange after blur only.
                if ($.browser.msie) {
                    $this.click(function() {
                        this.blur();
                    });
                }
            }
            // Detach any editor when the containing form is submitted.
            $('#' + params.field).parents('form').submit(function(event) {
                // Do not detach if the event was cancelled.
                if (event.originalEvent.returnValue === false) {
                    return;
                }
                Drupal.wysiwygDetach(context, params);
            });
        });
    };

    /**
     * Attach an editor to a target element.
     *
     * This tests whether the passed in editor implements the attach hook and
     * invokes it if available. Editor profile settings are cloned first, so they
     * cannot be overridden. After attaching the editor, the toggle link is shown
     * again, except in case we are attaching no editor.
     *
     * @param context
     *   A DOM element, supplied by Drupal.attachBehaviors().
     * @param params
     *   An object containing input format parameters.
     */
    Drupal.wysiwygAttach = function(context, params) {
        if (typeof Drupal.wysiwyg.editor.attach[params.editor] == 'function') {
            // (Re-)initialize field instance.
            Drupal.wysiwyg.instances[params.field] = {};
            // Provide all input format parameters to editor instance.
            jQuery.extend(Drupal.wysiwyg.instances[params.field], params);
            // Provide editor callbacks for plugins, if available.
            if (typeof Drupal.wysiwyg.editor.instance[params.editor] == 'object') {
                jQuery.extend(Drupal.wysiwyg.instances[params.field], Drupal.wysiwyg.editor.instance[params.editor]);
            }
            // Store this field id, so (external) plugins can use it.
            // @todo Wrong point in time. Probably can only supported by editors which
            //   support an onFocus() or similar event.
            Drupal.wysiwyg.activeId = params.field;
            // Attach or update toggle link, if enabled.
            if (params.toggle) {
                Drupal.wysiwygAttachToggleLink(context, params);
            }
            // Otherwise, ensure that toggle link is hidden.
            else {
                $('#wysiwyg-toggle-' + params.field).hide();
            }
            // Attach editor, if enabled by default or last state was enabled.
            if (params.status) {
                Drupal.wysiwyg.editor.attach[params.editor](context, params, (Drupal.settings.wysiwyg.configs[params.editor] ? jQuery.extend(true, {}, Drupal.settings.wysiwyg.configs[params.editor][params.format]) : {}));
            }
            // Otherwise, attach default behaviors.
            else {
                Drupal.wysiwyg.editor.attach.none(context, params);
                Drupal.wysiwyg.instances[params.field].editor = 'none';
            }
        }
    };

    /**
     * Detach all editors from a target element.
     *
     * @param context
     *   A DOM element, supplied by Drupal.attachBehaviors().
     * @param params
     *   An object containing input format parameters.
     */
    Drupal.wysiwygDetach = function(context, params) {
        var editor = Drupal.wysiwyg.instances[params.field].editor;
        if (jQuery.isFunction(Drupal.wysiwyg.editor.detach[editor])) {
            Drupal.wysiwyg.editor.detach[editor](context, params);
        }
    };

    /**
     * Append or update an editor toggle link to a target element.
     *
     * @param context
     *   A DOM element, supplied by Drupal.attachBehaviors().
     * @param params
     *   An object containing input format parameters.
     */
    Drupal.wysiwygAttachToggleLink = function(context, params) {
        if (!$('#wysiwyg-toggle-' + params.field).length) {
            var text = document.createTextNode(params.status ? Drupal.settings.wysiwyg.disable : Drupal.settings.wysiwyg.enable);
            var a = document.createElement('a');
            $(a).attr({id: 'wysiwyg-toggle-' + params.field, href: 'javascript:void(0);'}).append(text);
            var div = document.createElement('div');
            $(div).addClass('wysiwyg-toggle-wrapper').append(a);
            $('#' + params.field).after(div);
        }
        $('#wysiwyg-toggle-' + params.field)
                .html(params.status ? Drupal.settings.wysiwyg.disable : Drupal.settings.wysiwyg.enable).show()
                .unbind('click.wysiwyg', Drupal.wysiwyg.toggleWysiwyg)
                .bind('click.wysiwyg', {params: params, context: context}, Drupal.wysiwyg.toggleWysiwyg);

        // Hide toggle link in case no editor is attached.
        if (params.editor == 'none') {
            $('#wysiwyg-toggle-' + params.field).hide();
        }
    };

    /**
     * Callback for the Enable/Disable rich editor link.
     */
    Drupal.wysiwyg.toggleWysiwyg = function(event) {
        var context = event.data.context;
        var params = event.data.params;
        if (params.status) {
            // Detach current editor.
            params.status = false;
            Drupal.wysiwygDetach(context, params);
            // After disabling the editor, re-attach default behaviors.
            // @todo We HAVE TO invoke Drupal.wysiwygAttach() here.
            Drupal.wysiwyg.editor.attach.none(context, params);
            Drupal.wysiwyg.instances[params.field] = Drupal.wysiwyg.editor.instance.none;
            Drupal.wysiwyg.instances[params.field].editor = 'none';
            $(this).html(Drupal.settings.wysiwyg.enable).blur();
        }
        else {
            // Before enabling the editor, detach default behaviors.
            Drupal.wysiwyg.editor.detach.none(context, params);
            // Attach new editor using parameters of the currently selected input format.
            Drupal.wysiwyg.getParams($('.wysiwyg-field-' + params.field + ':checked, div.wysiwyg-field-' + params.field, context).get(0), params);
            params.status = true;
            Drupal.wysiwygAttach(context, params);
            $(this).html(Drupal.settings.wysiwyg.disable).blur();
        }
    }

    /**
     * Parse the CSS classes of an input format DOM element into parameters.
     *
     * Syntax for CSS classes is "wysiwyg-name-value".
     *
     * @param element
     *   An input format DOM element containing CSS classes to parse.
     * @param params
     *   (optional) An object containing input format parameters to update.
     */
    Drupal.wysiwyg.getParams = function(element, params) {
        var classes = element.className.split(' ');
        var params = params || {};
        for (var i = 0; i < classes.length; i++) {
            if (classes[i].substr(0, 8) == 'wysiwyg-') {
                var parts = classes[i].split('-');
                var value = parts.slice(2).join('-');
                params[parts[1]] = value;
            }
        }
        // Convert format id into string.
        params.format = 'format' + params.format;
        // Convert numeric values.
        params.status = parseInt(params.status, 10);
        params.toggle = parseInt(params.toggle, 10);
        params.resizable = parseInt(params.resizable, 10);
        return params;
    };

    /**
     * Allow certain editor libraries to initialize before the DOM is loaded.
     */
    Drupal.wysiwygInit();

})(jQuery);
